Disable Audio Units plug-ins

If you're having an issue in a particular Logic Pro project or MainStage concert, note the third-party plug-ins you're using in the affected project. Then, try disabling the plug-ins one-by-one using the Plug-In Manager, testing the project after disabling each plug-in.

Open Logic Pro or MainStage. In MainStage, you must open a concert to access the Plug-In Manager. In Logic Pro, make sure to turn on Show Advanced Tools.

Remove Audio Units plug-ins

If you suspect a particular plug-in, locate the file for the plug-in in the folder, the drag the file to the Desktop.

Try to reopen the app.

If you still can't open Logic Pro or MainStage:

Create a new folder on the Desktop.

Move all the plug-in files that appear in their installation locations to the new folder.

Try to open Logic Pro or MainStage.

If you can open the app, replace each plug-in file to its original location one-by-one. Quit and reopen the app after you replace each plug-in file. If you can't open the app after replacing a particular plug-in file, that plug-in might be corrupted or incompatible. Try reinstalling the disabled plug-in, or check with the manufacturer for an update.

Restart your Mac

If your Mac is running macOS High Sierra and you recently installed a plug-in that isn't available in Logic Pro or MainStage, restart your Mac. Before you restart your Mac, confirm that the plug-in is 64-bit compatible.*

Choose Apple menu > Restart.

Open Logic Pro or MainStage, and check to see if the plug-in is available in your project or concert. If the plug-in still isn't available, rescan the plug-in.

* 32-bit plug-ins aren't compatible with Logic Pro or MainStage.

Confirm that the plug-in is installed

If you can't find the recently installed plug-in in Logic Pro or MainStage after restarting your Mac, confirm that the plug-in is installed:

Restart the computer, then open Logic Pro X or MainStage. All installed Audio Unit plug-ins will be rescanned.

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